Liquid diets may be an option for many reasons, but the amount of exercise that is appropriate for your diet plan has more to do with daily calories. Exercise burns energy and that is an important part of managing your weight. Whether you eat solid food or exist solely on a liquid sustenance, you must eat enough calories each day to stay healthy. There is no hard-and-fast rule that says you can't exercise if you are on a liquid diet. The answer depends on a number of factors. Talk to your doctor before beginning any restricted diet program and discuss how much exercise you need.
Exercise and Weight Loss
Dieting and exercise are partners for healthy weight loss. When you eat more calories then your body needs, the excess is stored as fat. To lose weight, you must tip the scale in the other direction and burn more calories then you eat. This way, your body dips into the fat reserve for energy. If a person needs 2,000 calories just to function each day but only takes in 1,500, then that person will lose one pound fat in seven days. By adding exercise into the equation, the number of calories you burn goes up and the weight comes off faster.
Daily Calorie Counts
The problem with many commercial liquid diet plans is that they reduce daily calories so low that exercise cannot be part of the equation. A very low calorie diet would be below 1,000 calories a day. UT Southwestern Medical Center provides a liquid diet with 1,000 calories and they do recommend exercise to improve the chances of success. With anything below 1,000 calories, your body may try to protect itself by slowing your metabolism to prevent starvation. Exercise requires energy. If your body thinks it is starving, you may not have that energy. Low calorie liquid diets should be medically supervised. This will ensure you receive the nutrients you need to stay healthy and take in enough calories. A medically-sponsored plan will also guide you regarding exercise.
The Mayo Clinic reports the average person requires 46 to 56 grams of protein a day. Not all liquid diets are low in calories. Many commercial programs use protein shakes as the liquid substance. Adding additional protein to your day may actually increase your intake because protein is a calorie dense food. With protein shakes in a liquid diet, exercise may be a critical to burn off extra calories.
If a doctor suggests a liquid diet is right for you, the program will probably increase your activity level at some point. Exercise may be necessary, but that decision will depend on your health. Overall, liquid diets for weight loss can deprive you of the nutrients contained in whole foods and may not be any more effective than balanced meals with plenty of vegetables, whole grains and lean protein. If a liquid diet is necessary as a medical treatment, then a dietitian or doctor will set the exercise parameters for you.
UT Southwestern Medical Center: Liquid Protein Diet Program
Mayo Clinic: Weight Loss: Counting Calories: Get Back to Weight-Loss Basics
Mayo Clinic: Protein Shakes: Good for Weight Loss: Katherine Zeratsky, R.D., L.D.
University of Iowa Hospitals and Clinics: Fasting and Liquid Diets